Dear DataMed user: DataMed prototype(v3.0) is being developed for the NIH BD2K Data Discovery Index (DDI) by the bioCADDIE project team. DataMed, once completed, will be of use to the scientific community to allow users to search for and find data across different repositories in one space.
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Thank you, from the bioCADDIE team.

Background: Trisomy 21 causes Down syndrome (DS), but the mechanisms by which the extra chromosome leads to deficient intellectual and immune function are not well understood. Results: Here, we profile CpG methylation in DS and control cerebral and cerebellar cortex of adults and cerebrum of fetuses. We purify neuronal and non-neuronal nuclei and T-lymphocytes and find biologically relevant genes with DS-specific methylation (DS-DM) in brain cells. Some genes show brain-specific DS-DM, while others show stronger DS-DM in T cells. Both 5-methyl-cytosine and 5-hydroxy-methyl-cytosine contribute to the DS-DM. Thirty percent of genes with DS-DM in adult brain cells also show DS-DM in fetal brains, indicating early onset of these epigenetic changes, and we find early maturation of methylation patterns in DS brain and lymphocytes. Some, but not all, of the DS-DM genes show differential expression. DS-DM preferentially affected CpGs in or near specific transcription factor binding sites, implicating a mechanism involving altered transcription factor binding. Methyl-seq of brain DNA from mouse models with sub-chromosomal duplications mimicking DS reveals partial but significant overlaps with human DS-DM and shows that multiple chromosome 21 genes contribute to the downstream epigenetic effects. Conclusions: These data point to novel biological mechanisms in DS and have general implications for trans effects of chromosomal duplications and aneuploidies on epigenetic patterning. Bisulfite converted DNA from 119 samples from Down syndrome patients and controls were hybridised to the Illumina Infinium 450k Human Methylation Beadchip. In addition, we re-analyzed 6 Down syndrome and 6 control cerebellum DNA samples on the 450K BeadChips using an adaptation of the Illumina probe preparation protocol (TrueMethyl kit; Cambridge Epigenetics, CEGX), in which parallel analyses of bisulfite and oxidative bisulfite DNA for each sample allows assessment of the relative contributions of 5mC and 5hmC to net methylation.